Zidormi is still missing for many players in Vale of Eternal Blossoms.
Because of this entering the Ny’alotha, the Waking City raid isn’t possible every other week when the entrance to this raid is in this specific zone.
My recollection is that you need to complete some of the BFA story line for her to appear in the vale. I don’t think it’s a bug; it’s always been this way. I recommend checking wowhead for the specifics.